consecutive numeric character references

[Gene McCulley]

There is a bug in XMLParser when parsing consecutive numeric character 
references because UNESCAPE_UNICODE_PATTERN greedily matches.

We found this when exchanging JSON snippets over chat. The chat client was 
turning the preceding whitespace in a JSON snippet into 
     and this causes XMLParser to throw an exception trying 
to parse it as one character instead of as four characters.

Here is a patch. (I'm not sure if this is the best approach. Maybe it would be 
better to make the whole expression lazy?):

diff --git a/nbxml/src/main/java/org/apache/vysper/xml/sax/impl/XMLParser.java 
b/nbxml/src/main/java/org/apache/vysper/xml/sax/impl/XML
index 96ca040..6be4bb4 100644
--- a/nbxml/src/main/java/org/apache/vysper/xml/sax/impl/XMLParser.java
+++ b/nbxml/src/main/java/org/apache/vysper/xml/sax/impl/XMLParser.java
@@ -54,7 +54,7 @@ public class XMLParser implements TokenListener {
 
     public static final Pattern NAME_PREFIX_PATTERN = Pattern.compile("^xml", 
Pattern.CASE_INSENSITIVE);
 
-    public static final Pattern UNESCAPE_UNICODE_PATTERN = 
Pattern.compile("\\&\\#(x?)(.+);");
+    public static final Pattern UNESCAPE_UNICODE_PATTERN = 
Pattern.compile("\\&\\#(x?)([0-9a-fA-F]++);");
 
     private ContentHandler contentHandler;
 
diff --git 
a/nbxml/src/test/java/org/apache/vysper/xml/sax/impl/ParseTextTestCase.java 
b/nbxml/src/test/java/org/apache/vysper/xml/sax/
index 5305a9b..2f3112e 100644
--- a/nbxml/src/test/java/org/apache/vysper/xml/sax/impl/ParseTextTestCase.java
+++ b/nbxml/src/test/java/org/apache/vysper/xml/sax/impl/ParseTextTestCase.java
@@ -88,6 +88,18 @@ public class ParseTextTestCase extends 
AbstractAsyncXMLReaderTestCase {
         assertFalse(events.hasNext());
     }
 
+    public void testConsecutiveUnicodeEscape() throws Exception {
+        Iterator<TestEvent> events = 
parse("<root>&#160;&#160;&#160;&#160;</root>").iterator();
+
+        assertStartDocument(events.next());
+        assertStartElement("", "root", "root", events.next());
+        assertText("\u00A0\u00A0\u00A0\u00A0", events.next());
+        assertEndElement("", "root", "root", events.next());
+        assertEndDocument(events.next());
+
+        assertFalse(events.hasNext());
+    }
+
     public void testTextOnly() throws Exception {
         Iterator<TestEvent> events = parse("text</root>").iterator();